Publications by authors named "Yong-Zheng Chen"

20 Publications

  • Page 1 of 1

Design, synthesis, and herbicidal activity of novel phenoxypyridine derivatives containing natural product coumarin.

Pest Manag Sci 2021 Jun 23. Epub 2021 Jun 23.

Department of Chemistry, College of Arts and Sciences, Northeast Agricultural University, Harbin, China.

Background: In recent years, protoporphyrinogen oxidase (PPO, EC 1.3.3.4) inhibitors have been widely studied as important agricultural herbicides. Our research focused on the design and synthesis of novel PPO inhibitor herbicides, through linking of a diphenylether pyridine bioisostere structure to substituted coumarins, which aims to enhance environmental and crop safety while retaining high efficacy.

Results: A total of 21 compounds were synthesized via acylation reactions and all compounds were characterized using infrared, H NMR, C NMR, and high-resolution mass spectra. The respective configurations of compounds IV-6 and IV-12 were also confirmed using single crystal X-ray diffraction. The bioassay results showed that the title compounds displayed notable herbicidal activity, particularly compound IV-6 which displayed better herbicidal activity in greenhouse and field experiments, crop selectivity and safety for cotton and soybean compared with the commercial herbicide oxyfluorfen.

Conclusion: The work revealed that compound IV-6 deserves further attention as a candidate structure for a novel and safe herbicide.
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http://dx.doi.org/10.1002/ps.6523DOI Listing
June 2021

Palladium-catalyzed asymmetric allylic alkylation of 3-aminooxindoles to access chiral homoallylic aminooxindoles.

Org Biomol Chem 2021 Jun;19(21):4720-4725

Key Laboratory of Biocatalysis & Chiral Drug Synthesis of Guizhou Province, School of Pharmacy, Zunyi Medical University, Zunyi 563000, China. and Key Laboratory of Basic Pharmacology of Ministry of Education and Joint International Research Laboratory of Ethnomedicine of Ministry of Education, Zunyi Medical University, Zunyi 563000, China.

An organometal catalytic conversion of 3-aminooxindoles for the diastereo- and enantioselective synthesis of homoallylic aminooxindoles has been described. The asymmetric allylic alkylation of 3-aminooxindoles with allyl carboxylates proceeded smoothly to afford a series of chiral 3-allyl-3-aminooxindoles. This work offers an alternative route to build these scaffolds. The application of this protocol is also highlighted by a significant conversion of products to the potential applicable spiro[indoline-3,2'-pyrrolidin]-2-one derivatives.
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http://dx.doi.org/10.1039/d1ob00550bDOI Listing
June 2021

Catalytic Enantioselective Dearomatization/Rearomatization of 2-Nitroindoles to Access 3-Indolyl-3'-Aryl-/Alkyloxindoles: Application in the Formal Synthesis of Cyclotryptamine Alkaloids.

Org Lett 2020 09 28;22(18):7088-7093. Epub 2020 Aug 28.

Institute for Advanced Study, Chengdu University, Chengdu 610106, China.

The first catalytic enantioselective dearomatization/rearomatization of 2-nitroindoles triggered by the Michael addition of 3-monosubstituted oxindoles was established. A wide range of 3-indolyl-3'-alkyloxindoles (up to 99% yield, 97% ee) and 3-indolyl-3'-aryloxindoles (up to 95% yield, 99% ee) were obtained by using an organocatalyst. This method provides an unprecedented strategy to access structurally diverse 3,3'-disubstituted oxindoles bearing a sterically congested triaryl-containing all-carbon quaternary stereocenter. The utility of this approach was verified by the formal synthesis of cyclotryptamine alkaloids.
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http://dx.doi.org/10.1021/acs.orglett.0c02350DOI Listing
September 2020

Synthesis of chromone-containing polycyclic compounds via palladium-catalyzed [2 + 2 + 1] annulation.

Org Biomol Chem 2020 02 27;18(6):1112-1116. Epub 2020 Jan 27.

Key Laboratory of Biocatalysis & Chiral Drug Synthesis of Guizhou Province, Generic Drug Research Center of Guizhou Province, Green Pharmaceuticals Engineering Research Center of Guizhou Province, School of Pharmacy, Zunyi Medical University, Zunyi 563006, P. R. China. and Key Laboratory of Basic Pharmacology of Ministry of Education and Joint International Research Laboratory of Ethnomedicine of Ministry of Education, Zunyi Medical University, Zunyi 563006, P. R. China.

A palladium-catalyzed [2 + 2 + 1] domino annulation of 3-iodochromones, α-bromo carbonyl compounds, and tetracyclododecene (TCD) is described. This approach provides a facile, efficient and atom-economical route to a variety of chromone-containing polycyclic compounds bearing fused/bridged-ring systems in good yields (up to 81%) with excellent diastereoselectivities (99 : 1 dr in all cases).
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http://dx.doi.org/10.1039/c9ob02690hDOI Listing
February 2020

Generation of Difluorodiazoethane (CFHCHN): Application in the Regioselective Synthesis of CFH-Containing Pyrazoles.

Org Lett 2019 11 23;21(21):8751-8755. Epub 2019 Oct 23.

Key Laboratory of Biocatalysis & Chiral Drug Synthesis of Guizhou Province, Generic Drug Research Center of Guizhou Province, School of Pharmacy , Zunyi Medical University , Zunyi 563006 , P. R. China.

A new method for the generation of difluorodiazoethane (CFHCHN) and a procedure for its efficient use in [3 + 2] cycloaddition with nitroolefins by the AcOH/O catalyst system were developed by using a simple two-chamber system. The method provides a facile and straightforward access to a series of 4-substituted 5-difluoromethyl-3-nitro-1-pyrazoles that are of interest in medicinal chemistry. Interestingly, the key factor for the success of this method is the efficient preparation of CFHCHN by an process.
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http://dx.doi.org/10.1021/acs.orglett.9b03371DOI Listing
November 2019

2,2-Bifunctionalization of Norbornene in Palladium-Catalyzed Domino Annulation.

Org Lett 2019 11 22;21(21):8857-8860. Epub 2019 Oct 22.

Key Laboratory of Biocatalysis & Chiral Drug Synthesis of Guizhou Province, Generic Drug Research Center of Guizhou Province, School of Pharmacy , Zunyi Medical University , Zunyi 563006 , PR China.

A palladium-catalyzed three-component [2 + 3 + 1] domino annulation among 3-iodochromones, α-bromoacetophenones, and norbornene is presented, affording various chromone-containing polycyclic compounds bearing fused/spiro/bridged-ring systems. For the first time, the 2,2-bifunctionalization of norbornene was realized in palladium-catalyzed domino reaction. This cyclization characterizes three new bonds (two C-C and one C-O) in a single operation and produces nontrivial spiro-norbornane fragments in comparison with a traditional palladium-catalyzed process involving norbornene.
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http://dx.doi.org/10.1021/acs.orglett.9b03565DOI Listing
November 2019

Organocatalyzed Asymmetric Dearomative Aza-Michael/Michael Addition Cascade of 2-Nitrobenzofurans and 2-Nitrobenzothiophenes with 2-Aminochalcones.

J Org Chem 2019 04 25;84(7):4381-4391. Epub 2019 Mar 25.

National Engineering Research Center of Chiral Drugs, Chengdu Institute of Organic Chemistry , Chinese Academy of Sciences , Chengdu 610041 , China.

An organocatalyzed dearomative aza-Michael/Michael addition cascade of 2-nitrobenzofurans and 2-nitrobenzothiophenes with 2-aminochalcones has been developed, opening a new channel to access a series of optically active tetrahydrobenzofuro[3,2- b]quinolines and tetrahydrobenzo[4,5]thieno[3,2- b]quinolines bearing three contiguous stereocenters with excellent diastereo- and enantioselectivities (all cases >20:1 dr, up to 99% ee). This study features the first asymmetric dearomative cascade reaction of 2-nitrobenzofurans and 2-nitrobenzothiophenes beginning with aza-Michael addition. The potential applications of the methodology were demonstrated by the preparative-scale experiment and the versatile transformations of the products.
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http://dx.doi.org/10.1021/acs.joc.9b00401DOI Listing
April 2019

Organocatalytic Asymmetric [3 + 2] Cycloaddition of N-2,2,2-Trifluoroethylisatin Ketimines with β-Trifluoromethyl Electron-Deficient Alkenes: Access to Vicinally Bis(trifluoromethyl)-Substituted 3,2'-Pyrrolidinyl Spirooxindoles.

Org Lett 2018 08 25;20(15):4453-4457. Epub 2018 Jul 25.

Chengdu Institute of Organic Chemistry , Chinese Academy of Sciences , Chengdu , 610041 , China.

N-2,2,2-Trifluoroethylisatin ketimines with β-trifluoromethyl enones, 3-trifluoroethylidene oxindole, and 3-trifluoroethylidene benzofuranone can undergo asymmetric [3 + 2] cycloaddition, catalyzed by chiral bifunctional squaramide-tertiary amine catalysts, affording a wide spectrum of 3,2'-pyrrolidinyl spirooxindoles. The significance of this protocol is highlighted by its extremely high efficiency in the construction of the structurally diverse spirocyclic oxindoles, bearing a vicinally bis(trifluoromethyl)-substituted pyrrolidine moiety, including four contiguous stereocenters, in high yields with excellent stereocontrol.
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http://dx.doi.org/10.1021/acs.orglett.8b01730DOI Listing
August 2018

Asymmetric [3 + 2] Cycloaddition Reaction of Isatin-Derived MBH Carbonates with 3-Methyleneoxindoles: Enantioselective Synthesis of 3,3'-Cyclopentenyldispirooxindoles Incorporating Two Adjacent Quaternary Spirostereocenters.

J Org Chem 2018 09 11;83(17):10465-10475. Epub 2018 Jul 11.

Generic Drug Research Center of Guizhou Province, School of Pharmacy , Zunyi Medial University , Zunyi 563000 , China.

A highly regio- and stereoselective [3 + 2] cycloaddition reaction for constructing novel 3,3'-cyclopentenyldispirooxindoles incorporating two adjacent quaternary spirostereocenters is reported. Under the mild conditions, the asymmetric annulation of isatin-derived MBH carbonates with 3-methyleneoxindoles involving a chiral tertiary amine catalyst provides the corresponding dispirooxindole frameworks with an extraordinary level of enantioselective control. Further synthetic utility of this method was demonstrated by the gram-scale experiment and simple transformation of the obtained product. Moreover, a plausible mechanism for this annulation reaction was also proposed on the basis of the control experiments.
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http://dx.doi.org/10.1021/acs.joc.8b01506DOI Listing
September 2018

A Protocol for the Synthesis of CFH-Containing Pyrazolo[1,5- c]quinazolines from 3-Ylideneoxindoles and in Situ Generated CFHCHN.

J Org Chem 2018 06 4;83(12):6556-6565. Epub 2018 Jun 4.

Generic Drug Research Center of Guizhou Province, Green Pharmaceuticals Engineering Research Center of Guizhou Province, School of Pharmacy , Zunyi Medical University , Zunyi 563000 , China.

Herein is disclosed a selective and facile approach for the construction of CFH-containing pyrazolo[1,5- c]quinazolines from easily accessible 3-ylideneoxindoles and in situ generated CFHCHN. The reaction involving a [3 + 2] cycloaddition/1,3-H shift/rearrangement/dehydrogenation cascade proceeded smoothly at room temperature in the absence of catalyst and additive. Moreover, this metal-free process along with mild conditions is desirable and valuable for the pharmaceutical industry. Importantly, this reaction features a broad substrate scope, good functional group tolerance, and gram-scale synthesis.
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http://dx.doi.org/10.1021/acs.joc.8b00866DOI Listing
June 2018

Organocatalyzed Enantioselective Conjugated Addition of Sodium Bisulfite to β-Trifluoromethyl-α,β-unsaturated Ketones.

J Org Chem 2018 05 30;83(10):5771-5777. Epub 2018 Apr 30.

National Engineering Research Center of Chiral Drugs, Chengdu Institute of Organic Chemistry , Chinese Academy of Sciences , Chengdu 610041 , China.

An efficient organocatalyzed enantioselective conjugated addition of sodium bisulfite to β-trifluoromethyl-α,β-unsaturated ketones using a cinchona alkaloid-derived squaramide catalyst is presented. A series of optically active sulfonic acids, bearing a tertiary stereocenter connecting a CF group and a SOH group, were obtained in excellent yields with high enantioselectivities (up to 99% yield and 97% ee) under mild conditions. This method will provide an efficient, economic, and green route to access chiral sulfonic acid compounds.
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http://dx.doi.org/10.1021/acs.joc.8b00171DOI Listing
May 2018

An asymmetric organocatalytic vinylogous Mannich reaction of 3-methyl-5-arylfuran-2(3H)-ones with N-(2-pyridinesulfonyl) imines: enantioselective synthesis of δ-amino γ,γ-disubstituted butenolides.

Org Biomol Chem 2018 03;16(10):1636-1640

Institute for Advanced Study, Chengdu University, Chengdu 610106, China.

An asymmetric organocatalytic vinylogous Mannich reaction of 3-methyl-5-arylfuran-2(3H)-ones with N-(2-pyridinesulfonyl)imines has been developed with 5 mol% thiourea-tertiary amine as the catalyst. A series of δ-amino γ,γ-disubstituted butenolides bearing adjacent quaternary and tertiary stereocenters are efficiently obtained with satisfactory results (up to 90% yield, 90 : 10 dr, and 95 : 5 er).
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http://dx.doi.org/10.1039/c7ob03117cDOI Listing
March 2018

Diastereoselective [3 + 2] cycloaddition of 3-ylideneoxindoles with in situ generated CFHCHN: syntheses of CFH-containing spirooxindoles.

Org Biomol Chem 2017 Jul;15(26):5571-5578

Generic Drug Research Center of Guizhou Province, School of Pharmacy, Zunyi Medical University, Zunyi, 563000, China.

An efficient [3 + 2] cycloaddition of 3-ylideneoxindoles with in situ generated CFHCHN for the syntheses of spirooxindoles has been developed. This methodology gives access to a range of relatively complex spirooxindoles featuring a CFH group and three contiguous stereogenic centers in up to 84% yield and 99 : 1 trans/cis.
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http://dx.doi.org/10.1039/c7ob01266gDOI Listing
July 2017

[A new bibenzyl compound from Dendrobium nobile].

Yao Xue Xue Bao 2016 07;51(7):1117-20

In this study, seven bibenzyl compounds were isolated from the stem of Dendrobium nobile by silica gel, MCI column chromatographic and preparative HPLC technology. By using spectroscopic techniques including NMR and MS, these compounds were identified as 4,α-dihydroxy-3,5,3’-trimethoxybibenzyl (1), 4,5-dihydroxy-3,3’,α-trimethoxybibenzyl (2), 4,4’-dihydroxy-3,5,3’-trimethoxybibenzyl (3), 4,5-dihydroxy-3,3’-dimethoxybibenzyl(4), 4,3’-dihydroxy-3,5-dimethoxybibenzyl (5), 5,4’-dihydroxy-3,3’-dimethoxybibenzyl (6) and 5,3’-dihydroxy-3-methoxybibenzyl (7). Compound 1 is a new compound and compound 4 was isolated from this plant for the first time.
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July 2016

Congenital Aural Stenosis: Clinical Features and Long-term Outcomes.

Sci Rep 2016 06 3;6:27063. Epub 2016 Jun 3.

Eye &ENT Hospital, Fudan University, Department of Otolaryngology-Head and Neck Surgery, Shanghai, 200032, China.

The aim of the present study was to comprehensively evaluate the clinical features and long-term outcomes of congenital aural stenosis (CAS). This study presents a retrospective review of patients who underwent meatoplasty for CAS at a tertiary referral hospital from 2008 to 2015. A total of 246 meatoplasty procedures were performed on 232 patients in the present study. We performed multivariate regression analysis. Except in the age < 6 years group, no significant difference was observed among different age groups for cholesteatoma formation, p > 0.05. Except for the stenosis of the external auditory canal (EAC) (>4 mm) group, the other stenosis of EAC groups were not associated with cholesteatoma formation, p > 0.05. Postoperative air-bone gaps (ABG) less than 30 dB occurred in 77.3% (99/128) of the patients, and the Jahrsdoerfer score was associated with postoperative ABG, p < 0.001. The complication rate of CAS was 13.8% (20/144), and males showed a higher risk for postoperative complications (OR, 6.563; 95% CI, 1.268-33.966, p = 0.025). These results indicate that meatoplasty was an effective surgical intervention for CAS, showing a stable hearing outcome with prolonged follow-up. There was no significant difference between the cholesteatoma and no cholesteatoma groups for hearing outcomes, p > 0.05.
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http://dx.doi.org/10.1038/srep27063DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4891728PMC
June 2016

Rheological and functional properties of composite sweet potato - wheat dough as affected by transglutaminase and ascorbic acid.

J Food Sci Technol 2016 Feb 23;53(2):1178-88. Epub 2015 Nov 23.

The State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122 China.

Effect of transglutaminase (TGM) and ascorbic acid (AA) on composite sweet potato - wheat dough functional and rheological properties was studied. Partial substitution of wheat flour with sweet potato flour at the level of 20 % significantly (P ≤ 0.05) reduced glutenin, gliadin, dough stability, protein weakening, storage modulus (G') and viscous modulus (G″). Mixolab revealed that both TGM and AA treated dough had stability and protein weakening closed to wheat dough (control), with TGM treated dough having the highest values. TGM Introduced new cross-link bonds as shown by the change of amino acid concentration, leading to an increase in storage modulus (G') and viscous modulus (G″), with G' being higher at all levels of TGM concentration. The opposite was observed for composite dough treated with AA as measured by controlled - stress rheometer. TGM treatment increased glutenin and gliadin content. Compared with the control, dough treated with AA exhibited high molecular weight of polymers than TGM treated dough. The results indicate that the TGM and AA modification of the mixolab and dynamic rheological characteristics (G' and G″) dependent on the changes of GMP, glutenin, gliadin and protein weakening in the composite dough. TGM and AA treatment could improve functional and rheological properties of sweet potato - wheat dough to levels that might be achieved with normal wheat bread. However, it's extremely important to optimize the concentrations of both additives to obtain the optimum response.
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http://dx.doi.org/10.1007/s13197-015-2004-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4837746PMC
February 2016

RNA-seq transcriptome analysis of a Pseudomonas strain with diversified catalytic properties growth under different culture medium.

Microbiologyopen 2016 08 6;5(4):626-36. Epub 2016 Apr 6.

School of Pharmacy, Zunyi Medical University, Zunyi, 563000, China.

Biocatalysis is an emerging strategy for the production of enantio-pure organic molecules. However, lacking of commercially available enzymes restricts the widespread application of biocatalysis. In this study, we report a Pseudomonas strain which exhibited versatile oxidation activity to synthesize chiral sulfoxides when growing under M9-toluene medium and reduction activity to synthesize chiral alcohols when on Luria-Bertani (LB) medium, respectively. Further comparative transcriptome analysis on samples from these two cultural conditions has identified 1038 differentially expressed genes (DEG). Gene Ontology (GO) enrichment and KEGG pathways analysis demonstrate significant changes in protein synthesis, energy metabolism, and biosynthesis of metabolites when cells cultured under different conditions. We have identified eight candidate enzymes from this bacterial which may have the potential to be used for synthesis of chiral alcohol and sulfoxide chemicals. This work provides insights into the mechanism of diversity in catalytic properties of this Pseudomonas strain growth with different cultural conditions, as well as candidate enzymes for further biocatalysis of enantiomerically pure molecules and pharmaceuticals.
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http://dx.doi.org/10.1002/mbo3.357DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4985596PMC
August 2016

An unprecedented protocol for the synthesis of 3-hydroxy-3-phenacyloxindole derivatives with indolin-2-ones and α-substituted ketones.

Org Biomol Chem 2016 Jan 16;14(4):1395-401. Epub 2015 Dec 16.

National Engineering Research Center of Chiral Drugs, Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, China.

An unprecedented reaction between indolin-2-ones and α-substituted ketones has been developed. Using this protocol, a wide range of biologically important 3-hydroxy-3-phenacyloxindole derivatives could be obtained in good yield (up to 93%) under mild reaction conditions. A possible mechanism of this reaction was tentatively proposed based on some control experiments and MS spectrometry analysis.
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http://dx.doi.org/10.1039/c5ob02391bDOI Listing
January 2016

[Design, synthesis and antitumor activities of novel E-substituted 2,3-diaryl propenoic acyloxy phosphonate derivatives].

Yao Xue Xue Bao 2015 Apr;50(4):464-8

According to the super-position principle of the reinforcement of biological activities, a series of novel E-substituted 2, 3-diaryl propenoic acyloxy phosphonate derivatives were designed and synthesized. And the structures of the target compounds were confirmed by IR, 1H NMR, 13C NMR and elemental analysis. Furthermore, the cytotoxicities of all compounds on A-549, SGC-7901 and EC-109 in vitro were evaluated by MTT assay, and some of them showed good antitumor activity. Among the active compounds, especially, the IC50 value of compound 3e was (12.7 ± 1.9) μmol x L(-1) against A-549 cells, similar to cisplatin [IC50 = (8.0 ± 1.5) μmol x L(-1)], compounds 3g and 3k had better inhibition effect on EC-109 cells growth, with the IC50 values of (9.5 ± 1.8) μmol x L(-1) and (11.5 ± 0.9) μmol x L(-1) respectively, and compounds 3i and 3k exhibited good cytotoxic property on A-549, SGC-7901 and EC-109, which were worth further investigation.
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April 2015

The frequency response of a floating piezoelectric microphone for the implantable middle ear microphone.

Laryngoscope 2013 Jun 26;123(6):1506-13. Epub 2013 Apr 26.

Department of Otolaryngology, Eye and ENT Hospital, Fudan University, Shanghai, China.

Objectives/hypothesis: A piezoelectric sensor, floating piezoelectric microphone, driven by acoustic vibration of the ossicles, is one possible design for a microphone for a totally implantable cochlear implant. The purpose of the article was to study the frequency response of the floating piezoelectric microphone and to identify the ideal feasible position in the ossicular chain.

Study Design: Basic Research.

Methods: The frequency response of the floating piezoelectric microphone was analyzed by finite-element modeling and in vitro testing of fresh cadaveric heads. The floating piezoelectric microphone, 5.0 mm in length and 1.5 mm by 1.2 mm in rectangular cross section, as a piezoelectric microphone, was placed at various locations on the ossicular chain and stimulated by pure tones of different frequencies.

Results: The floating piezoelectric microphone can pick up the vibration of the ossicular chain and effectively convert it into the electronic signals effectively both in the long process of incus and in the malleus. The average sensitivity of the FPM is -44.22 dB rms ref 1V at 1000 Hz in the long process of incus, -53.33 dB rms ref 1V at 1000 Hz in the malleus, and -108.59 dB rms ref 1V at 1000 Hz in the tympanic cavity.

Conclusions: The floating piezoelectric microphone is expected to be used as an implantable middle ear microphone for the totally implantable cochlear implant.
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http://dx.doi.org/10.1002/lary.23618DOI Listing
June 2013
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